Injectable fibrin composition for bone augmentation

ABSTRACT

The present invention relates to a biodegradable injectable composition for bone augmentation comprising fibrin, a contrast agent and calcium salt-containing particles, as well as a method for bone augmentation in a patient suffering from a bone disorder comprising injecting said composition into a non-mineralized or hollow portion of said bone.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. Nonprovisional PatentApplication No. 11/736,518, filed Apr. 17, 2007, which is anonprovisional of, and claims the benefit of priority to, U.S.Provisional Patent Application No. 60/808,802 filed May 26, 2006. Theentire content of each of the aforementioned applications isincorporated herein by reference for all purposes.

FIELD OF THE INVENTION

The present invention relates to a biodegradable injectable compositionfor bone augmentation comprising fibrin, a contrast agent and calciumsalt-containing particles, as well as a method for bone augmentation ina patient suffering from a bone disorder comprising injecting saidcomposition into a non-mineralized or hollow portion of said bone.

BACKGROUND

For example, percutaneous bone augmentation includes the techniques ofvertebroplasty and kyphoplasty which have been used in the followingindications: painful hemangiomas, osteoporotic compression fractures,traumatic compression fractures and painful vertebral metastasis. Anexample is the percutaneous delivery of polymethylmethacrylate (PMMA)bone cements to repair fractured vertebral bodies. This treatment iseffective in relieving pain and restoring height to the vertebrae. Thetargeted vertebrae are identified using fluoroscopy and a trocar needleis introduced into the vertebral body. The PMMA can be delivered to one(unilateral) or both (bilateral) sides of the vertebral body and thedelivery is monitored using fluoroscopy to ensure that the cementremains a bolus, without leakage or migration.

Complications of the technique include leakage of PMMA. This can beparavertebral leakage, venous infiltration, epidural leakage andintradiscal leakage (Truckai C., Shadduck J.H., US 2006089715, 2006).Leakage can result in very serious complications including compressionof adjacent structures (requiring further surgery) and/or embolism.Recent research has also demonstrated that a mismatching of forcesbetween the PMMA and natural bone leads to an increase in secondaryfractures in the vertebrae adjacent to the PMMA treatment (Trout A.T.,Kallmes D.F., Kaufmann T.J., Journal of Neuroradiology, 2006,27:217-223).

A further complication of the technique is the high exothermicity ofPMMA that can potentially cause heat necrosis extending to the duralsac, cord and nerve roots. This exothermicity also limits the ability ofPMMA to incorporate any pharmacological or chemotherapeutic agents. PMMAis also a non-resorbable material and is capable of leaching unreacted,unpolymerised and low molecular weight chemicals. For the technique afluoroscopic contrast agent (usually barium sulphate) is incorporated inthe PMMA cements to facilitate the fluoroscopic delivery. The long termeffects of barium sulphate on the bone and the cement properties are notfully known.

The viscosity of PMMA is also a critical parameter. It must be lowenough to permit injection and high enough to prevent it from beingsqueezed into the vasculature. The viscosity rises with time providingthe clinician with a window of approximately 10 minutes to perform thetechnique and retrieve the needle.

Thus, a strong need exists for injectable bone augmentation compositionswhich overcome the above-mentioned disadvantages.

Therefore, it is an object of the present invention to provide newinjectable compositions for bone augmentation, such as in vertebroplastyand kyphoplasty.

SUMMARY

The present invention relates to a micro-porous injectable fullyresorbable, i.e. biologically degradable, fibrin matrix. The material ofthe present invention has substantially no exothermicity, exhibitsmechanical properties typically seen in elastomers and is mechanicallysuperior to fibrin alone. Adequate radio-opacity is achieved through theincorporation of suitable contrast agents and viscosity is achieved orcontrolled through the incorporation of a particulate species. UnlikePMMA, in certain embodiments the starting material of the presentinvention gels rapidly and can be delivered with negligible waitingtime. It does not have an upper time limit for completion of thetechnique allowing more time to deliver the material.

DETAILED DESCRIPTION

One aspect of the present invention relates to a multi-component systemfor an injectable bone augmentation composition, comprising:

component (a) comprising fibrinogen;

component (b) comprising thrombin;

component (c) comprising at least one contrast agent; and

component (d) comprising at least one type of calcium salt-containingparticles having a diameter of about 200 μm or less.

According to one embodiment of the present invention the components (a)to (d) of the multi-component system as defined above are each presentin solution, wherein at least component (a) is spacially separated fromcomponent (b).

The multi-component system for an injectable bone augmentationcomposition as defined above may further include any other componentsuitable for e.g. augmenting, strengthening, supporting, repairing,rebuilding, healing or filling a bone, such as osteoinductive agents,growth factors, chemotherapeutic or pharmacological agents, biologicallyactive agents, hardening and/or adhesive compounds and mineraladditives. These compounds may be contained in any of the components (a)to (d) of the multi-component system according to the present inventionor may be comprised as extra components.

According to one example of the present invention, the fibrinogencomponent (a) of the multi-component system as defined above may furthercomprise one or more of extracellular matrix proteins, for examplefibronectin, cellular associated proteins, other plasma derivedproteins, for example blood clotting factor XIII (FXIII) and proteases,and protease inhibitors, and mixtures thereof. The fibrinogen solutionaccording to the present invention may also include any additive whichis comprised in the state of the art for scientific and/or commerciallyavailable fibrinogen compositions, for example commercially availablefibrinogen solutions.

The term “fibrinogen” includes not only fibrinogen per se, but also anyclot-forming substance, such as clot-forming derivatives of fibrinogen,for example “fibrin1”.

The amount of fibrinogen in said fibrinogen component (a) of themulti-component system ranges for example from about 10 to about 200mg/ml, such as from about 30 to about 150 mg/ml or from about 75 toabout 115 mg/ml.

The thrombin component (b) of the multi-component system according tothe present invention, may further comprise additional compounds knownin the art as well as one or both of the components (c) and (d),particularly the contrast agent component (c). There is no specificlimitation in respect to the used thrombin amount. In one example of thepresent invention, the amount of thrombin in said thrombin component (b)is such that it is at least about 1 IU/ml in the final clottedcomposition, such as about 30 IU/ml.

The term “thrombin” includes not only thrombin per se, but also anygelation-inducing or clotting-inducing agent for component (a), forexample a physiologically acceptable alkaline buffer system.

The term “contrast agent”, as used herein, includes any suitablecontrast agent usable according to the present invention in imagingapplications known in the art such as fluoroscopy. In one embodiment ofthe present invention, the suitable contrast agent of themulti-component system as defined above has a low osmolality and allowsfibrin assembly to occur at an appropriate extent.

Further, the term “contrast agent” includes all such compounds which canbe used according to the present invention and can be distinguished froma surrounding tissue by detecting and/or applying radiation such asX-ray radiation, radioactive radiation, infrared radiation, ultravioletradiation, electron or neutron radiation, or a magnetic field, orultrasound, or any combination thereof.

In one example of the present invention, the suitable contrast agent ofthe multi-component system according to the present invention comprisesat least one iodine containing organic compound. In a further example ofthe present invention, organic compounds containing rare earth elementssuch as gadolinium can be used.

As used herein, the term “iodine containing organic compound” includesall compounds which contain at least one iodine atom and/or iodine ion,bonded either physically or chemically, for example covalently orcoordinatively. The same definition applies mutatis mutandis to theabove-mentioned organic compound containing rare earth elements.

Examples of suitable contrast agents of the multi-component system asdefined above are selected from the group consisting of diatrizoate(meglumine), iodecol, iodixanol, iofratol, iogulamide, iohexol,iomeprol, iopamidol, iopromide, iotrol, ioversol, ioxaglate andmetrizamide.

According to one example of the present invention, the amount ofcontrast agent such as iodixanol or iohexol in component (c) is suchthat it ranges from about 100 to about 800 mg/ml, such as from about 150to about 600 mg/ml or from about 200 to about 400 mg/ml, in the finalclotted composition.

The term “particle” includes any type of particle shape or form known inthe art, for example spherical, angular or hollow.

In one embodiment of the present invention, the calcium salt-containingparticles of the multi-component system according to the presentinvention are selected from the group consisting of tricalciumphosphate, alpha-tricalcium phosphate, beta-tricalcium phosphate,calcium phosphate, a polymorph of calcium phosphate, hydroxyapatite,calcium carbonate, calcium sulfate and combinations thereof. Forexample, said calcium salt-containing particles are selected from thegroup consisting of tricalcium phosphate, alpha-tricalcium phosphate,beta-tricalcium phosphate and calcium phosphate, having a Ca/P ratio inthe range from about 1.5 to about 2. The calcium salt-containingparticles of the present invention further include all commerciallyavailable compounds and/or mixtures known in the art to be used withinthe meaning of component (d). According to another example, said calciumsalt-containing particles of the multi-component system of the presentinvention have a diameter of less than about 100 μm, for example of lessthan about 50 μm. In one specific example of the present invention theamount of the particles in component (d) ranges from about 1 to about50% w/w, such as from about 10 to about 45% w/w or from about 30 to 40%w/w in respect to the final clotted composition.

According to one embodiment of the present invention, the amount offibrinogen in component (a) of the multi-component system as definedabove ranges from about 10 to about 200 mg/ml, the amount of thrombin incomponent (b) is such that it is at least about 1 IU/ml in the finalclotted composition, the amount of contrast agent contained in component(c) is such that it ranges from about 100 to about 800 mg/ml in thefinal clotted composition, and the amount of the at least one type ofcalcium salt-containing particles in component (d) ranges from about 1to about 50% w/w in respect to the final clotted composition.

According to a specific example of the present invention, the amount offibrinogen in component (a) of the multi-component system as definedabove ranges from about 75 to about 115 mg/ml, the amount of thrombin incomponent (b) is such that it ranges from about 25 IU/ml to about 50IU/ml in the final clotted composition, the amount of contrast agentcontained in component (c) is such that it ranges from about 300 toabout 500 mg/ml in the final clotted composition, and the amount of theat least one type of calcium salt containing particles in component (d)ranges from about 30 to about 40% w/w in respect to the final clottedcomposition.

In another embodiment of the present invention, the multi-componentsystem for an injectable bone augmentation composition, comprises:

component (a) comprising fibrinogen;

component (b) comprising thrombin;

component (c) comprising at least one contrast agent; and

component (d) comprising at least one type of calcium salt-containingparticles having a diameter of about 200 μm or less; wherein one or moreor all of the components (a) to (d) are present in a solid form.

The multi-component system according to the present invention maycontain the components either in form of a solution or of a dispersionor of a solid, for example as a lyophilisate, or any combinationthereof. Further, the components in said multi-component system may bepresent in containers suitable for storage, transportation or use ofsaid multi-component system. The containers usable in themulti-component system according to the present invention are notlimited in any way but include containers of any size, material orshape, for example vials or syringes.

Moreover, the components of said multi-component system may for examplebe contained in different containers or may be present in the samecontainer in any combination, for example as a combination of components(b) and (c) in one container and of components (a) and (d) each indifferent containers.

According to the present invention, the containers may for examplecontain one or more components as a solid, as well as a solventseparated from said components by a separation means in said container,wherein a solution of the respective one or more components can beprepared by breaking or removing said separation means. The components(a) to (d) of the multi-component system of the present invention may bealso present as a ready-to-use mixture.

Moreover, said components (a) to (d) present in one or more containersmay also be part of a kit, comprising the multi-component system asdefined above. The kit may further comprise any additional compoundusable in the multi-component system of the present invention, forexample auxiliary agents, buffer salts or buffer solutions. The kit asdefined above may also contain means for mixing the components, forexample syringes, Luer adapters, tubes, extra containers, etc.

Another aspect of the present invention relates to an injectable boneaugmentation composition, comprising:

component (a) comprising fibrin;

component (b) comprising thrombin;

component (c) comprising at least one contrast agent; and

component (d) comprising at least one type of calcium salt-containingparticles having a diameter of about 200 μm or less.

According to one example of the present invention, the injectable boneaugmentation composition is prepared from the multi-component system asdefined above, for example by mixing the components of saidmulti-component system together and/or homogenizing said components. Thepreparation of the injectable bone augmentation composition can becarried out at any suitable temperature, such as in the range from about18 to about 37° C., for example at 25° C.

Moreover, the injectable bone augmentation composition as defined abovemay further include any other component suitable for e.g. augmenting,strengthening, supporting, repairing, rebuilding, healing or filling abone, such as osteoinductive agents, growth factors, chemotherapeutic orpharmacological agents, biologically active agents, hardening and/oradhesive compounds and mineral additives. These compounds and/or agentscan be chemically attached to the matrix, adsorbed on the particulatecomponent, for example on the calcium containing particles, trapped inthe fibrin matrix or contained as a free molecule/drug particle, forexample a powder.

The components (b) to (d) of the injectable bone augmentationcomposition according to the present invention are the same as definedfor the multi-component system characterized above.

The term “fibrin” does not only refer to fully coagulated fibrinogen butfurther includes any mixture of fibrin and fibrinogen which may occurduring formation of fibrin from fibrinogen using thrombin and, thus,includes any ratio of fibrinogen/fibrin and any grade of gelation and/orclotting conceivable as long as it has no negative impact on the finalcomposition injected into the non-mineralized or hollow portion of thebone. The fibrin component (a) of the injectable bone augmentationcomposition of the present invention further includes fibrin with only asmall amount of fibrinogen or without any fibrinogen left in saidfibrin. Moreover, the term “fibrin” further includes any partly or fullygelled or clotted form of component (a) as defined above.

According to one example of the present invention, the amount of fibrinin said fibrin component (a) of the injectable bone augmentationcomposition as defined above ranges from about 5 to about 100 mg/ml,such as from about 15 to 65 mg/ml or from about 30 to 65 mg/ml in thefinal clotted composition.

According to another example, the amount of fibrin in said fibrincomponent (a) of the injectable bone augmentation composition of thepresent invention ranges from about 5 to about 100 mg/ml in the finalclotted composition, the amount of thrombin in said thrombin component(b) is at least about 1 IU/ml in the final clotted composition, theamount of contrast agent contained in said contrast agent component (c)ranges from about 100 to about 800 mg/ml in the final clottedcomposition, and the amount of the at least one calcium salt-containingparticles in component (d) ranges from about 1 to about 50% w/w inrespect to the final clotted composition.

According to the present invention, the injectable bone augmentationcomposition as defined above is in a gelled or clotted state and has aviscosity suitable for injecting into a non-mineralized or hollowportion of a bone, and may be applied in a pre-clotted liquid, gelled orclotted state.

As used herein, the term “gelled” means any state of elevated viscositywhen compared to the initial state. This can be observed for example inthe formation of fibrin from fibrinogen or in a finely dispersed systemof at least one solid phase and at least one liquid phase, such as acolloid. Further, the term “gelled” includes all states of gelationknown in the art.

The term “clotted” means, for example, a gel comprising fibrin andincludes any kind of coagulation state known in the art.

According to the present invention, the viscosity of the injectablecomposition depends on the application, i.e. the bone disorder to betreated, and is adjusted within the common knowledge of a person skilledin the art. For example, an injectable composition for filling bonecysts contains a lower fibrin amount and/or a lower amount of calciumsalt-containing particles. An injectable composition for replacingnon-mineralized portions of the bone contains a higher fibrin amountand/or a higher amount of calcium salt-containing particles.

Another aspect of the present invention, relates to a method ofaugmenting a bone in a patient suffering from a bone disorder,comprising injecting the injectable bone augmentation composition ascharacterized above, into a non-mineralized or hollow portion of saidbone.

As used herein, the term “patient” means a subject suffering from a bonedisorder and includes mammals, particularly human beings.

The method of augmenting a bone as defined above is not limited to acertain mode of treatment and includes any kind of injection technique,for example percutaneous injection. According to a specific example ofthe present invention, the method for augmenting a bone as defined aboveis percutaneous vertebral augmentation and comprises vertebroplasty andkyphoplasty.

Moreover, the method of augmenting a bone according to the presentinvention can be used for strengthening, supporting, repairing,rebuilding, healing or filling a bone, for example a bone in a humansuffering from a bone disorder.

Examples of such bone disorders are osteoporosis for example invertebra, hip and fore-arm, or benign and malignant lesions.

The injectable bone augmentation composition according to the presentinvention is surprisingly advantageous in that it allows injection intoa non-mineralized or hollow portion of a bone while the procedure can bemonitored by a variety of imaging methods such as fluoroscopy. This facteffectively enables the surgeon/physician to verify the injectedcomposition is in correct place and therefore advantageously avoidssevere problems such as leakage of the composition into the blood streamof the patient. Moreover, the addition of calcium salt containingparticles to the fibrin based composition surprisingly enhances thecontrast given by the contrast agent contained in said composition,thereby advantageously allowing a reduction of the content of saidcontrast agent. Other beneficial characteristics of the compositioncomprise the highly advantageous biodegradability of the final clottedcomposition, the ease of handling and, particularly in form of themulti-component system, long term storage stability and highavailability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: Differences in complex viscosities as a result of increasingconcentration of contrast agent and/or the particulate content.

FIG. 2: Injection of the injectable bone augmentation composition intoosteoporotic bones to increase local bone production in vertebra (left)and femoral head (right).

The present invention will be further illustrated in the followingexamples, without any limitation thereto.

EXAMPLES Example 1: Preparation of Clots Containing Iodinated ContrastAgent and Particles Materials:

Fibrin sealant solution Freeze dried fibrinogen powder reconstitutedwith aprotinin solution to a total clottable protein concentration of 91mg/ml.

Iodixanol5-[acetyl-[3-[acetyl-[3,5-bis(2,3-dihydroxypropylcarbamoyl)-2,4,6-triiodo-phenyl]-amino]-2-hydroxy-propyl]-amino]-N,N′-bis(2,3-dihydroxypropyl)-2,4,6-triiodo-benzene-1,3-dicarboxamide

Iohexol5-(acetyl-(2,3-dihydroxypropyl)amino)-N,N′-bis(2,3-dihydroxypropyl)-2,4,6-triiodo-benzene-1,3-dicarboxamide

Particles Tricalcium phosphate particles (TCP), 35 μm, spherical (PlasmaBiotal, Derby UK)

Thrombin 500 IU/ml Freeze dried thrombin powder reconstituted with 5 mlof thrombin buffer, to a concentration of 500 IU/ml.

Thrombin Buffer 40 mM CaCl₂ in H₂O

Either an 80% or a 60% contrast agent (iodixanol or iohexol) and a 75IU/ml thrombin solution is prepared in a thrombin dilution buffer (40 mMCaCl₂ in double distilled water). The solution is then homogenised. Thesolution is centrifuged to remove bubbles and sterilised by filteringthrough a 0.22 μm filter. The fibrinogen is mixed with thrombin/contrastagent (CA) in a 1:1 ratio (therefore the CA concentration in the gelledclot is halved to either 40 or 30%). For this 2 ml of thethrombin/contrast agent solution is transferred to a 5 ml syringe. 2 mlof fibrinogen (91 mg/ml) is transferred to a separate 5 ml syringe. Theparticles (ca. 2 μm) are incorporated as percentage weight of the finalclot volume (w/v). These are weighed and placed into another 5 mlsyringe.

The syringes containing the particles and the thrombin are connected viaa Luer adapter and the thrombin/CA and particles homogenised bytransferring the contents from syringe to syringe thoroughly.

The syringes containing the thrombin/CA/particles and the fibrinogen areconnected via a Luer adapter and the contents homogenised.

The material remains liquid for approximately 1 minute during this timeit can be injected into the defect or alternatively after a few minutesit can be delivered as a pre-formed gel.

The viscosities of respective clots with different concentrations ofcontrast agents and of TCP can be taken from FIG. 1.

Example 2: Mechanical Behaviour of Fibrin Clots in the Presence orAbsence of a Contrast Agent

Clots containing iodinated contrast agent and particles are prepared asdescribed in Example 1. These clots are cast in wells of amultiwell-plate where they are then allowed to gel. These clots areremoved from the wells, and their mechanical properties are then testedin compression using a universal mechanical testing system.

On visual inspection, there is a big difference between normal fibrinclots and CA clots prepared according to Example 1. The contrast agentcontaining clots are clear and transparent while the normal fibrin clotsare white and opaque. Like the normal fibrin clots the CA clots can beinjected into a mould following a brief mixing and allowed to gel.Differences between normal clots and CA clots can be observed duringthis process. The normal clots are easily damaged, collapse and leakbuffer while being retrieved from the mold. The CA clots remain intactand can be handled more forcefully. These materials also exhibitelasticity and this is demonstrated using non-confined uni-axialcompressive testing. In this test the normal clots reach ca. 80% strainbefore stress begins to increase. At the point at which the stress risesthe clot is near to being completely squashed and the buffer forced out.Conversely CA clots are much stiffer and after 20% strain begin to showan increase in stress i.e. a greater force is needed to compress themand this continues to rise until the clot breaks. If the stress isremoved at any point prior to the break the clot returns to its originalshape, unlike the normal clots which are permanently damaged. It is alsoobserved that with longer “gelling” times the clots have fewertendencies to break as they become even more elastic. This often resultsin experiments having to be stopped as the clots are expelled from theInstron (mechanical testing machine) due to the build up of storedenergy.

Example 3: Application of the Injectable Bone Augmentation Composition

Osteoporosis and age related loss in bone mineral density often leads tofractures in vertebra and femoral head. Injection of the injectable boneaugmentation composition according to the present invention at thesesites helps in the treatment of such injuries. The formulations of theinjectable bone augmentation compositions are prepared as outlined inExample 1.

Under fluoroscopy (C-arm) a vertebroplasty trocar (diameter: 3.2 mm(10G) or 1.8 mm (15 G), length 100 or 150 mm) is placed in a vertebra and afemoral head, respectively, of a human cadaver using the transpedicularapproach.

TCP is added to the contrast agent containing thrombin solution byswooshing the two components back and forth until homogenization (about20 times).

The TCP and contrast agent containing thrombin solution is mixed withthe fibrinogen solution by swooshing the solutions back and forthapprox. 6 times in two connected syringes. After gelation the material(approx. 9 ml) is loaded into the barrel of a vertebroplasty gun(Optimed Cemento RE).

The gun is directly connected to the trocar (without a tube in between)and the material is applied to the vertebra and to the femoral head,respectively, by screwing it out of the gun. During the procedurespictures were taken (cf. FIG. 2).

Example 4: In Vivo Studies of The Injectable Bone AugmentationComposition in Sheep

The medial fascia of the tibia shaft is excised and the tibia isexposed. A plate is contoured to the shaft and fixed to the bone usingscrews. The plate is removed again and a standardized 1 cm fullthickness defect is created. The segment is removed, the plate isrepositioned and the screws are reinserted. Thereafter, the injectablebone augmentation composition is filled into the defect and the wound isclosed by suture.

The animals are followed up for 4, 8 and 12 weeks (X-ray evaluation). Atthe 12 weeks timepoint the animals are sacrificed and the tibia isextracted for final analysis (μCT and histology).

The contrast agent had no negative impact on the medical effect of theclot inside the bone.

What is claimed is:
 1. A method of augmenting a bone in a patient havinga bone disorder, the method comprising injecting a composition to atreatment site of the patient, the composition comprising: component (a)comprising fibrin; component (b) comprising thrombin; component (c)comprising at least one contrast agent; and component (d) comprising atleast one type of calcium salt-containing particles having a diameter ofabout 200 μm or less, wherein the treatment site comprises anon-mineralized or hollow portion of the bone.
 2. The method ofaugmenting a bone according to claim 1, wherein the bone disorder isselected from the group consisting of osteoporosis in vertebra,osteoporosis in the hip, osteoporosis in the fore-arm, a benign lesion,and a malignant lesion.
 3. The method of augmenting a bone according toclaim 1, wherein the at least one contrast agent is selected from thegroup consisting of iodixanol and iohexol, and the amount of the atleast one contrast agent is from 300 to 400 mg/ml in the composition. 4.A method of treating a bone in a patient having a bone disorder,comprising injecting a composition into a non-mineralized or hollowportion of the bone, the composition comprising: component (a)comprising fibrin; component (b) comprising thrombin; and component (c)comprising at least one contrast agent selected from the groupconsisting of iodixanol and iohexol, wherein the amount of contrastagent is from 300 to 400 mg/ml in the composition.
 5. The method oftreating bone according to claim 4, wherein treating the bone comprisesaugmenting the bone.
 6. The method of treating bone according to claim4, wherein treating the bone comprises strengthening, supporting,repairing, rebuilding, healing, or filling the bone.
 7. The method oftreating bone according to claim 4, wherein treating the bone comprisesfilling bone cysts or replacing non-mineralized portions of a bone. 8.The method of treating bone according to claim 4, wherein injecting thecomposition is by percutaneous injection
 9. The method of treating boneaccording to claim 4, wherein: the composition further comprisescalcium-salt particles, and the calcium salt-containing particles areselected from the group consisting of tricalcium phosphate,alpha-tricalcium phosphate, beta-tricalcium phosphate, calciumphosphate, a polymorph of calcium phosphate, hydroxyapatite, calciumcarbonate, calcium sulfate, and any combinations thereof.
 10. The methodof treating bone according to claim 4, wherein: the composition furthercomprises calcium-salt particles, the calcium salt-containing particlesare selected from the group consisting of tricalcium phosphate,alpha-tricalcium phosphate, beta-tricalcium phosphate and calciumphosphate, and mixtures thereof, and/or the calcium salt-containingparticles have a Ca/P ratio in the range of about 1.5 to about
 2. 11.The method of treating bone according to claim 4, wherein the amount offibrin in component (a) ranges from about 5 to about 100 mg/ml in thecomposition.
 12. The method of treating bone according to claim 4,wherein the amount of thrombin in component (b) is at least 1 IU/ml inthe composition.
 13. The method of treating bone according to claim 4,wherein the amount of fibrin in component (a) ranges from about 5 toabout 100 mg/ml in the composition, and the amount of thrombin incomponent (b) is at least about 1 IU/ml in the composition.
 14. Themethod of treating bone according to claim 4, wherein the composition isin a gelled or clotted state.
 15. The method of treating bone accordingto claim 4, wherein: the composition further comprises calciumsalt-containing particles, and the salt-containing particles range fromabout 1 to about 50% w/w in respect to the composition.
 16. The methodof treating bone according to claim 4, wherein: the composition furthercomprises calcium salt-containing particles, and the calciumsalt-containing particles have a diameter of less than about 100 μm. 17.The method of treating bone according to claim 4, wherein: thecomposition further comprises calcium salt-containing particles, and thecalcium salt-containing particles have a diameter of less than about 50μm.
 18. The method of treating bone according to claim 4, wherein: thecomposition further comprises calcium salt-containing particles, and thecalcium salt-containing particles range from about 10 to about 45% w/win respect to the composition.
 19. The method of treating bone accordingto claim 4, wherein: the composition further comprises calciumsalt-containing particles, and the calcium salt-containing particlesrange from about 30 to about 40% w/w in respect to the composition. 20.A method of treating a bone in a patient having a bone disorder,comprising: mixing components of a multi-component system to form a bonetreatment composition, the multi-component system comprising: component(a) comprising fibrinogen, component (b) comprising thrombin, andcomponent (c) comprising a contrast agent selected from the groupconsisting of iodixanol and iohexol, wherein the amount of the contrastagent is from 300 to 400 mg/ml in the composition; and injecting thebone treatment composition into a non-mineralized or hollow portion ofthe bone.
 21. The method of treating the bone according to claim 20,wherein mixing the components comprises transferring the componentsbetween two syringes.
 22. The method of treating the bone according toclaim 20, wherein one or more or all of the components (a) to (c) arepresent in a solid form.
 23. The method of treating the bone accordingto claim 20, wherein the amount of fibrinogen in the fibrinogencomponent (a) ranges from about 10 to about 200 mg/ml.
 24. The method oftreating the bone according to claim 20, wherein component (a) comprisesthe fibrinogen at a concentration of 91 mg/ml, and component (b)comprises thrombin at a concentration of 75 IU/ml.